Corrosion-resistant and malleable alloy



Patented July 2, 1935 UNITED STATES PA 'lEN'l OFFICE CORROSION-RESISTANT AND ALLOY No Drawing. Application February 2'1,

Serial No. 8,486. In Austria July 8, 1932 4 (liaims.

This invention relates to corrosion-resistant and malleable alloys and constitutes a continuation in part of our application, Serial No. 678,- 4'72, filed June 30, 1933.

5 Gamma-brass, that is tosay, cbpper-zinc-alloys containing from 31 to 40% of copper, are known in the literature. Such alloys are distinguished by a low copper content, and are more corrosion-resistant than the generally used brass alloys of high copper content of the alpha and alpha+beta fields, and. containing for example, 68 to 72% of copper. It is, however, impossible to employ the gamma-alloys, poor in copper, industrially, since these alloys are extraordinarily hard and brittle, and can therefore not be worked.

The surprising observation has now been made in accordance with the present invention, that by the simultaneous addition of nickel and cobalt alloys are obtained which exhibit the excellent anti-corrosion properties of the gamma-alloys, but which are admirably adapted to be mechanically worked. 4

Particularly useful are alloys which contain said additional metals in an amount from three to ten per cent, that is to say alloys containing from 3 to 10% of cobalt and nickel jointly.

The simultaneous employment of cobalt and nickel enables the same effect to be obtained with a substantially smaller cobalt content than when using cobalt alone.

Particularly useful are alloys according to the invention, which comprise an addition of from one to six per cent of cobalt and from four to nine per cent of nickel, the amount of the added metals being within their solubility limits in gamma-brass.

The alloys of the present invention are also distinguished by a high resistance to erosion.

The following is an example of compositions of alloysin accordance with the invention, the parts being given by weight:-

38 to 33% of copper,

l to 6% of cobalt, Approximately 4% of nickel,

' Remainder zinc. 10

What we claim is:

1. Corrosion-resistant, mechanically workable alloys, which consist substantially of a copperzinc alloy containing copper in an amount corresponding to gamma-brass and an addition of from three to ten per cent of the elements cobalt and nickel jointly.

2. Corrosion-resistant, mechanically workable alloys according to claim 1, containing from one to six per cent of cobalt.

3. Corrosion-resistant, mechanically workable alloys according to claim 1, containing from four to nine per cent of nickel. I

4. Corrosion-resistant, mechanically workable alloy having the following composition:

Copper 33'to 38% Cobalt 1 to 6% Nickel about 4% mmremainder.

WOLF JOHANNESMfiLLER. MORITZ museum. 

